Blender Executable file
Executables on *nix-like Operating Systems in General
*nix-like operating systems usually don't use file extensions to determine if a file is executable or not. Instead they rely on file system flags and file headers (for example ELF headers for binaries and !# - aka Shebang - for shell scripts).
Without going too deep into technical details:
If you download Blender for Linux from blender.org and extract it on any GNU/Linux based operating system, all the necessary flags should be already set. You execute Blender by clicking (single/double depending on your UI settings) on the file called &quot;blender&quot;.